Ravana did not have actual 10 heads. It is said he Had knowledge equal to 10 persons. and ten times offered his head to shiva.
Australian team is called Kangaroo and new Zealand Kivi.
Are they also a fiction?
Krishna's city Dwarika is has been found under the sea. That is called Archeological evidence.see below:
" Dr S R Rao, formerly of the Archaeological Survey of India (ASI) and now with the National Institute of Oceanography in Goa. With all the existing limitations, he has done considerable work in the Bet Dwaraka region, where he found an entire submerged city, with rubble and masonry structures, several shell and pottery items and seals. The Mahabharata and Harivamsha describe Krishna‚s capital Dwaraka and how it was submerged by the sea in great detail, a description that coincides in many ways with what the divers found. Unfortunately, the doubting Thomases of our historical world, a school of Indian historians who regard Indian literature as, myth do not want to acknowledge this interpretation, in case it gives credence to the story of Krishna, whose capital was submerged by the sea. It is ridiculous not to correlate archaeology and literature. Mythology is, the science of primitive man, his manner of explaining the universe. Records of natural phenomena and historical events ˜ invasions, migrations, etc. ˜ are stored as myths. If literature and archaeology had not been correlated, we would never have known the history of ancient Greece. And how many people are aware of the fact that the only (ancient) temple for Matsya ˜ Vishnu's incarnation at the time of the great flood ˜ is to be found at Shankhodhara in Bet Dwaraka."
source: Marine archaeology and the study of the past - By Nanditha Krishn
http://www.atributetohinduism.com/Dwaraka.htm
So is ram setu by NASA. Chek out Adam's Bridge on net.
Writer's do use their imagination and make the stories colourfull.
Like Tulsi made Hanuman fly over the sea. In original Ramayana He swims across.
Mahabharat had too many stories inserted in it.
But the essential story has too many logical references to be rejected as all fiction.